This invention relates to the fastening device and to secure a farm implement or the like to a tractor or the like. A typical hitch unit includes a bushing member on the tractor, a shaft member on the implement, and a hitch pin which is coactable with the shaft member to lock the latter to the bushing member. As a tractor, under normal operations, is subjected to rough ground as it traverses a field, the hitch pin is dislodged from the shaft and the implement separates from the tractor. To overcome this disadvantage, hitch pins have been developed wherein a ring is secured off-center to the hitch pin and thereby closes against the pin in a position to discourage disengagement of the pin from the shaft. However, if there is any upstanding grain, weeds or foreign objects on the field, the ring becomes dislodged and the pin may jiggle out of its position relative to the shaft.
Other pins have been developed wherein a wire or spring is secured to the ring of the pin which coacts with the shank end of the pin to lock it to the shaft. These pins, however, take considerable abuse and break or are lost, thus any additional elements only increase the cost of replacement. Secondly, the ease of installation is affected and time is lost in engaging and disengaging the pin.